#ifndef HASHTABLE_H_
#define HASHTABLE_H_

#include "hash_fun.h"

#include <algorithm>
#include <vector>

_BEGIN_HS_NAMESPACE_

_USE_NAMESPACE_STD_

class DefaultAlloc
{
public:
	static void *allocate(size_t _size)
	{ 
		return (void *)malloc(_size);	
	}

	static void deallocate(void *__p, size_t __size = 0)
	{ 
		free(__p);
	}
};

template<class _Tp, class _Alloc = DefaultAlloc>
class simple_alloc {
public:
	static _Tp* allocate(size_t __n)
	{ 
		return 0 == __n ? 0 : (_Tp*) _Alloc::allocate(__n * sizeof (_Tp)); 
	}

	static _Tp* allocate(void)
	{ 
		return (_Tp*) _Alloc::allocate(sizeof (_Tp)); 
	}

	static void deallocate(_Tp* __p, size_t __n)
	{ 
		if (0 != __n) _Alloc::deallocate(__p, __n * sizeof (_Tp)); 
	}

	static void deallocate(_Tp* __p)
	{ 
		_Alloc::deallocate(__p, sizeof (_Tp)); 
	}
};

template <class _Val>
struct _Hashtable_node
{
	_Hashtable_node* _M_next;
	_Val _M_val;
};  

template <class _Val, class _Key, class _HashFcn,
class _ExtractKey, class _EqualKey, class _Alloc/* = alloc*/>
class hashtable;

template <class _Val, class _Key, class _HashFcn,
class _ExtractKey, class _EqualKey, class _Alloc>
struct _Hashtable_iterator;

template <class _Val, class _Key, class _HashFcn,
class _ExtractKey, class _EqualKey, class _Alloc>
struct _Hashtable_const_iterator;

template <class _Val, class _Key, class _HashFcn,
class _ExtractKey, class _EqualKey, class _Alloc>
struct _Hashtable_iterator 
{
	typedef hashtable<_Val,_Key,_HashFcn,_ExtractKey,_EqualKey,_Alloc>
		_Hashtable;

	typedef _Hashtable_iterator<_Val, _Key, _HashFcn, 
		_ExtractKey, _EqualKey, _Alloc>
		iterator;
	typedef _Hashtable_const_iterator<_Val, _Key, _HashFcn, 
		_ExtractKey, _EqualKey, _Alloc>
		const_iterator;

	typedef _Hashtable_node<_Val> _Node;

	typedef forward_iterator_tag iterator_category;
	typedef _Val value_type;
	typedef ptrdiff_t difference_type;
	typedef size_t size_type;
	typedef _Val& reference;
	typedef _Val* pointer;

	_Node* _M_cur;
	_Hashtable* _M_ht;

	_Hashtable_iterator(_Node* __n, _Hashtable* __tab) 
		: _M_cur(__n), _M_ht(__tab) {}
	_Hashtable_iterator() {}

	reference operator*() const { return _M_cur->_M_val; }
	pointer operator->() const { return &(operator*()); }

	iterator& operator++();
	iterator operator++(int);

	bool operator==(const iterator& __it) const
	{ return _M_cur == __it._M_cur; }
	bool operator!=(const iterator& __it) const
	{ return _M_cur != __it._M_cur; }
};


template <class _Val, class _Key, class _HashFcn,
class _ExtractKey, class _EqualKey, class _Alloc>
struct _Hashtable_const_iterator {
	typedef hashtable<_Val,_Key,_HashFcn,_ExtractKey,_EqualKey,_Alloc>
		_Hashtable;
	typedef _Hashtable_iterator<_Val,_Key,_HashFcn, 
		_ExtractKey,_EqualKey,_Alloc>
		iterator;
	typedef _Hashtable_const_iterator<_Val, _Key, _HashFcn, 
		_ExtractKey, _EqualKey, _Alloc>
		const_iterator;
	typedef _Hashtable_node<_Val> _Node;

	typedef forward_iterator_tag iterator_category;
	typedef _Val value_type;
	typedef ptrdiff_t difference_type;
	typedef size_t size_type;
	typedef const _Val& reference;
	typedef const _Val* pointer;

	const _Node* _M_cur;
	const _Hashtable* _M_ht;

	_Hashtable_const_iterator(const _Node* __n, const _Hashtable* __tab)
		: _M_cur(__n), _M_ht(__tab) {}
	_Hashtable_const_iterator() {}
	_Hashtable_const_iterator(const iterator& __it) 
		: _M_cur(__it._M_cur), _M_ht(__it._M_ht) {}
	reference operator*() const { return _M_cur->_M_val; }
	pointer operator->() const { return &(operator*()); }
	const_iterator& operator++();
	const_iterator operator++(int);
	bool operator==(const const_iterator& __it) const 
	{ return _M_cur == __it._M_cur; }
	bool operator!=(const const_iterator& __it) const 
	{ return _M_cur != __it._M_cur; }
};

// Note: assumes long is at least 32 bits.
enum { __stl_num_primes = 28 };

static const unsigned long __stl_prime_list[__stl_num_primes] =
{
	53ul,         97ul,         193ul,       389ul,       769ul,
	1543ul,       3079ul,       6151ul,      12289ul,     24593ul,
	49157ul,      98317ul,      196613ul,    393241ul,    786433ul,
	1572869ul,    3145739ul,    6291469ul,   12582917ul,  25165843ul,
	50331653ul,   100663319ul,  201326611ul, 402653189ul, 805306457ul, 
	1610612741ul, 3221225473ul, 4294967291ul
};

inline unsigned long __stl_next_prime(unsigned long __n)
{
	const unsigned long* __first = __stl_prime_list;
	const unsigned long* __last = __stl_prime_list + (int)__stl_num_primes;
	const unsigned long* pos = lower_bound(__first, __last, __n);
	return pos == __last ? *(__last - 1) : *pos;
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
class hashtable;

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
bool operator==(const hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>& __ht1,
				const hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>& __ht2);

template <class _Val, class _Key, class _HashFcn, 
class _ExtractKey, class _EqualKey, class _Alloc>
class hashtable {
public:
	typedef _Key key_type;
	typedef _Val value_type;
	typedef _HashFcn hasher;
	typedef _EqualKey key_equal;

	typedef size_t            size_type;
	typedef ptrdiff_t         difference_type;
	typedef value_type*       pointer;
	typedef const value_type* const_pointer;
	typedef value_type&       reference;
	typedef const value_type& const_reference;

	hasher hash_funct() const { return _M_hash; }
	key_equal key_eq() const { return _M_equals; }

private:
	typedef _Hashtable_node<_Val> _Node;

public:
	typedef _Alloc allocator_type;
	allocator_type get_allocator() const { return allocator_type(); }
private:
	typedef simple_alloc<_Node, _Alloc> _M_node_allocator_type;
	_Node* _M_get_node() { return _M_node_allocator_type::allocate(1); }
	void _M_put_node(_Node* __p) { _M_node_allocator_type::deallocate(__p, 1); }
# define __HASH_ALLOC_INIT(__a)

private:
	hasher                _M_hash;
	key_equal             _M_equals;
	_ExtractKey           _M_get_key;
	vector<_Node*,_Alloc> _M_buckets;
	size_type             _M_num_elements;

public:
	typedef _Hashtable_iterator<_Val,_Key,_HashFcn,_ExtractKey,_EqualKey,_Alloc>
		iterator;
	typedef _Hashtable_const_iterator<_Val,_Key,_HashFcn,_ExtractKey,_EqualKey,
		_Alloc>
		const_iterator;

	friend struct
		_Hashtable_iterator<_Val,_Key,_HashFcn,_ExtractKey,_EqualKey,_Alloc>;
	friend struct
		_Hashtable_const_iterator<_Val,_Key,_HashFcn,_ExtractKey,_EqualKey,_Alloc>;

public:
	hashtable(size_type __n,
		const _HashFcn&    __hf,
		const _EqualKey&   __eql,
		const _ExtractKey& __ext,
		const allocator_type& __a = allocator_type())
		: __HASH_ALLOC_INIT(__a)
		_M_hash(__hf),
		_M_equals(__eql),
		_M_get_key(__ext),
		_M_buckets(__a),
		_M_num_elements(0)
	{
		_M_initialize_buckets(__n);
	}

	hashtable(size_type __n,
		const _HashFcn&    __hf,
		const _EqualKey&   __eql,
		const allocator_type& __a = allocator_type())
		: __HASH_ALLOC_INIT(__a)
		_M_hash(__hf),
		_M_equals(__eql),
		_M_get_key(_ExtractKey()),
		_M_buckets(__a),
		_M_num_elements(0)
	{
		_M_initialize_buckets(__n);
	}

	hashtable(const hashtable& __ht)
		: __HASH_ALLOC_INIT(__ht.get_allocator())
		_M_hash(__ht._M_hash),
		_M_equals(__ht._M_equals),
		_M_get_key(__ht._M_get_key),
		_M_buckets(__ht.get_allocator()),
		_M_num_elements(0)
	{
		_M_copy_from(__ht);
	}

	hashtable& operator= (const hashtable& __ht)
	{
		if (&__ht != this) {
			clear();
			_M_hash = __ht._M_hash;
			_M_equals = __ht._M_equals;
			_M_get_key = __ht._M_get_key;
			_M_copy_from(__ht);
		}
		return *this;
	}

	~hashtable() { clear(); }

	size_type size() const
	{
		return _M_num_elements; 
	}

	size_type max_size() const 
	{ 
		return size_type(-1); 
	}

	bool empty() const
	{ 
		return size() == 0; 
	}

	void swap(hashtable& __ht)
	{
		__STD::swap(_M_hash, __ht._M_hash);
		__STD::swap(_M_equals, __ht._M_equals);
		__STD::swap(_M_get_key, __ht._M_get_key);
		_M_buckets.swap(__ht._M_buckets);
		__STD::swap(_M_num_elements, __ht._M_num_elements);
	}

	iterator begin()
	{ 
		for (size_type __n = 0; __n < _M_buckets.size(); ++__n)
			if (_M_buckets[__n])
				return iterator(_M_buckets[__n], this);
		return end();
	}

	iterator end() 
	{ 
		return iterator(0, this); 
	}

	const_iterator begin() const
	{
		for (size_type __n = 0; __n < _M_buckets.size(); ++__n)
			if (_M_buckets[__n])
				return const_iterator(_M_buckets[__n], this);
		return end();
	}

	const_iterator end() const 
	{ 
		return const_iterator(0, this); 
	}

	template <class _Vl, class _Ky, class _HF, class _Ex, class _Eq, class _Al>
	friend bool operator== (const hashtable<_Vl, _Ky, _HF, _Ex, _Eq, _Al>&,
		const hashtable<_Vl, _Ky, _HF, _Ex, _Eq, _Al>&);

public:

	size_type bucket_count() const 
	{ 
		return _M_buckets.size(); 
	}

	size_type max_bucket_count() const
	{ 
		return __stl_prime_list[(int)__stl_num_primes - 1]; 
	} 

	size_type elems_in_bucket(size_type __bucket) const
	{
		size_type __result = 0;
		for (_Node* __cur = _M_buckets[__bucket]; __cur; __cur = __cur->_M_next)
			__result += 1;
		return __result;
	}

	pair<iterator, bool> insert_unique(const value_type& __obj)
	{
		resize(_M_num_elements + 1);
		return insert_unique_noresize(__obj);
	}

	iterator insert_equal(const value_type& __obj)
	{
		resize(_M_num_elements + 1);
		return insert_equal_noresize(__obj);
	}

	pair<iterator, bool> insert_unique_noresize(const value_type& __obj);
	iterator insert_equal_noresize(const value_type& __obj);

#ifdef __STL_MEMBER_TEMPLATES
	template <class _InputIterator>
	void insert_unique(_InputIterator __f, _InputIterator __l)
	{
		insert_unique(__f, __l, __ITERATOR_CATEGORY(__f));
	}

	template <class _InputIterator>
	void insert_equal(_InputIterator __f, _InputIterator __l)
	{
		insert_equal(__f, __l, __ITERATOR_CATEGORY(__f));
	}

	template <class _InputIterator>
	void insert_unique(_InputIterator __f, _InputIterator __l,
		input_iterator_tag)
	{
		for ( ; __f != __l; ++__f)
			insert_unique(*__f);
	}

	template <class _InputIterator>
	void insert_equal(_InputIterator __f, _InputIterator __l,
		input_iterator_tag)
	{
		for ( ; __f != __l; ++__f)
			insert_equal(*__f);
	}

	template <class _ForwardIterator>
	void insert_unique(_ForwardIterator __f, _ForwardIterator __l,
		forward_iterator_tag)
	{
		size_type __n = 0;
		distance(__f, __l, __n);
		resize(_M_num_elements + __n);
		for ( ; __n > 0; --__n, ++__f)
			insert_unique_noresize(*__f);
	}

	template <class _ForwardIterator>
	void insert_equal(_ForwardIterator __f, _ForwardIterator __l,
		forward_iterator_tag)
	{
		size_type __n = 0;
		distance(__f, __l, __n);
		resize(_M_num_elements + __n);
		for ( ; __n > 0; --__n, ++__f)
			insert_equal_noresize(*__f);
	}

#else /* __STL_MEMBER_TEMPLATES */
	void insert_unique(const value_type* __f, const value_type* __l)
	{
		size_type __n = __l - __f;
		resize(_M_num_elements + __n);
		for ( ; __n > 0; --__n, ++__f)
			insert_unique_noresize(*__f);
	}

	void insert_equal(const value_type* __f, const value_type* __l)
	{
		size_type __n = __l - __f;
		resize(_M_num_elements + __n);
		for ( ; __n > 0; --__n, ++__f)
			insert_equal_noresize(*__f);
	}

	void insert_unique(const_iterator __f, const_iterator __l)
	{
		size_type __n = 0;
		distance(__f, __l, __n);
		resize(_M_num_elements + __n);
		for ( ; __n > 0; --__n, ++__f)
			insert_unique_noresize(*__f);
	}

	void insert_equal(const_iterator __f, const_iterator __l)
	{
		size_type __n = 0;
		distance(__f, __l, __n);
		resize(_M_num_elements + __n);
		for ( ; __n > 0; --__n, ++__f)
			insert_equal_noresize(*__f);
	}
#endif /*__STL_MEMBER_TEMPLATES */

	reference find_or_insert(const value_type& __obj);

	iterator find(const key_type& __key) 
	{
		size_type __n = _M_bkt_num_key(__key);
		_Node* __first;
		for ( __first = _M_buckets[__n];
			__first && !_M_equals(_M_get_key(__first->_M_val), __key);
			__first = __first->_M_next)
		{}
		return iterator(__first, this);
	} 

	const_iterator find(const key_type& __key) const
	{
		size_type __n = _M_bkt_num_key(__key);
		const _Node* __first;
		for ( __first = _M_buckets[__n];
			__first && !_M_equals(_M_get_key(__first->_M_val), __key);
			__first = __first->_M_next)
		{}
		return const_iterator(__first, this);
	} 

	size_type count(const key_type& __key) const
	{
		const size_type __n = _M_bkt_num_key(__key);
		size_type __result = 0;

		for (const _Node* __cur = _M_buckets[__n]; __cur; __cur = __cur->_M_next)
			if (_M_equals(_M_get_key(__cur->_M_val), __key))
				++__result;
		return __result;
	}

	pair<iterator, iterator> 
		equal_range(const key_type& __key);

	pair<const_iterator, const_iterator> 
		equal_range(const key_type& __key) const;

	size_type erase(const key_type& __key);
	void erase(const iterator& __it);
	void erase(iterator __first, iterator __last);

	void erase(const const_iterator& __it);
	void erase(const_iterator __first, const_iterator __last);

	void resize(size_type __num_elements_hint);
	void clear();

private:
	size_type _M_next_size(size_type __n) const
	{ 
		return __stl_next_prime(__n); 
	}

	void _M_initialize_buckets(size_type __n)
	{
		const size_type __n_buckets = _M_next_size(__n);
		_M_buckets.reserve(__n_buckets);
		_M_buckets.insert(_M_buckets.end(), __n_buckets, (_Node*) 0);
		_M_num_elements = 0;
	}

	size_type _M_bkt_num_key(const key_type& __key) const
	{
		return _M_bkt_num_key(__key, _M_buckets.size());
	}

	size_type _M_bkt_num(const value_type& __obj) const
	{
		return _M_bkt_num_key(_M_get_key(__obj));
	}

	size_type _M_bkt_num_key(const key_type& __key, size_t __n) const
	{
		return _M_hash(__key) % __n;
	}

	size_type _M_bkt_num(const value_type& __obj, size_t __n) const
	{
		return _M_bkt_num_key(_M_get_key(__obj), __n);
	}

	_Node* _M_new_node(const value_type& __obj)
	{
		_Node* __n = _M_get_node();
		__n->_M_next = 0;
		__STL_TRY {
			construct(&__n->_M_val, __obj);
			return __n;
		}
		__STL_UNWIND(_M_put_node(__n));
	}

	void _M_delete_node(_Node* __n)
	{
		destroy(&__n->_M_val);
		_M_put_node(__n);
	}

	void _M_erase_bucket(const size_type __n, _Node* __first, _Node* __last);
	void _M_erase_bucket(const size_type __n, _Node* __last);

	void _M_copy_from(const hashtable& __ht);

};

template <class _Val, class _Key, class _HF, class _ExK, class _EqK, 
class _All>
_Hashtable_iterator<_Val,_Key,_HF,_ExK,_EqK,_All>&
_Hashtable_iterator<_Val,_Key,_HF,_ExK,_EqK,_All>::operator++()
{
	const _Node* __old = _M_cur;
	_M_cur = _M_cur->_M_next;
	if (!_M_cur) {
		size_type __bucket = _M_ht->_M_bkt_num(__old->_M_val);
		while (!_M_cur && ++__bucket < _M_ht->_M_buckets.size())
			_M_cur = _M_ht->_M_buckets[__bucket];
	}
	return *this;
}

template <class _Val, class _Key, class _HF, class _ExK, class _EqK, class _All>
inline _Hashtable_iterator<_Val,_Key,_HF,_ExK,_EqK,_All>
_Hashtable_iterator<_Val,_Key,_HF,_ExK,_EqK,_All>::operator++(int)
{
	iterator __tmp = *this;
	++*this;
	return __tmp;
}

template <class _Val, class _Key, class _HF, class _ExK, class _EqK, class _All>
_Hashtable_const_iterator<_Val,_Key,_HF,_ExK,_EqK,_All>&
_Hashtable_const_iterator<_Val,_Key,_HF,_ExK,_EqK,_All>::operator++()
{
	const _Node* __old = _M_cur;
	_M_cur = _M_cur->_M_next;
	if (!_M_cur) {
		size_type __bucket = _M_ht->_M_bkt_num(__old->_M_val);
		while (!_M_cur && ++__bucket < _M_ht->_M_buckets.size())
			_M_cur = _M_ht->_M_buckets[__bucket];
	}
	return *this;
}

template <class _Val, class _Key, class _HF, class _ExK, class _EqK, class _All>
inline _Hashtable_const_iterator<_Val,_Key,_HF,_ExK,_EqK,_All>
_Hashtable_const_iterator<_Val,_Key,_HF,_ExK,_EqK,_All>::operator++(int)
{
	const_iterator __tmp = *this;
	++*this;
	return __tmp;
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
bool operator==(const hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>& __ht1,
				const hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>& __ht2)
{
	typedef typename hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::_Node _Node;
	if (__ht1._M_buckets.size() != __ht2._M_buckets.size())
		return false;
	for (int __n = 0; __n < __ht1._M_buckets.size(); ++__n) {
		_Node* __cur1 = __ht1._M_buckets[__n];
		_Node* __cur2 = __ht2._M_buckets[__n];
		for ( ; __cur1 && __cur2 && __cur1->_M_val == __cur2->_M_val;
			__cur1 = __cur1->_M_next, __cur2 = __cur2->_M_next)
		{}
		if (__cur1 || __cur2)
			return false;
	}
	return true;
}  

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
inline bool operator!=(const hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>& __ht1,
					   const hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>& __ht2) {
						   return !(__ht1 == __ht2);
}

template <class _Val, class _Key, class _HF, class _Extract, class _EqKey, 
class _All>
	inline void swap(hashtable<_Val, _Key, _HF, _Extract, _EqKey, _All>& __ht1,
	hashtable<_Val, _Key, _HF, _Extract, _EqKey, _All>& __ht2) {
		__ht1.swap(__ht2);
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
pair<typename hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::iterator, bool> 
hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::insert_unique_noresize(const value_type& __obj)
{
	const size_type __n = _M_bkt_num(__obj);
	_Node* __first = _M_buckets[__n];

	for (_Node* __cur = __first; __cur; __cur = __cur->_M_next) 
		if (_M_equals(_M_get_key(__cur->_M_val), _M_get_key(__obj)))
			return pair<iterator, bool>(iterator(__cur, this), false);

	_Node* __tmp = _M_new_node(__obj);
	__tmp->_M_next = __first;
	_M_buckets[__n] = __tmp;
	++_M_num_elements;
	return pair<iterator, bool>(iterator(__tmp, this), true);
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
typename hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::iterator 
hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::insert_equal_noresize(const value_type& __obj)
{
	const size_type __n = _M_bkt_num(__obj);
	_Node* __first = _M_buckets[__n];

	for (_Node* __cur = __first; __cur; __cur = __cur->_M_next) 
		if (_M_equals(_M_get_key(__cur->_M_val), _M_get_key(__obj))) {
			_Node* __tmp = _M_new_node(__obj);
			__tmp->_M_next = __cur->_M_next;
			__cur->_M_next = __tmp;
			++_M_num_elements;
			return iterator(__tmp, this);
		}

		_Node* __tmp = _M_new_node(__obj);
		__tmp->_M_next = __first;
		_M_buckets[__n] = __tmp;
		++_M_num_elements;
		return iterator(__tmp, this);
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
typename hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::reference 
hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::find_or_insert(const value_type& __obj)
{
	resize(_M_num_elements + 1);

	size_type __n = _M_bkt_num(__obj);
	_Node* __first = _M_buckets[__n];

	for (_Node* __cur = __first; __cur; __cur = __cur->_M_next)
		if (_M_equals(_M_get_key(__cur->_M_val), _M_get_key(__obj)))
			return __cur->_M_val;

	_Node* __tmp = _M_new_node(__obj);
	__tmp->_M_next = __first;
	_M_buckets[__n] = __tmp;
	++_M_num_elements;
	return __tmp->_M_val;
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
pair<typename hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::iterator,
typename hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::iterator> 
hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::equal_range(const key_type& __key)
{
	typedef pair<iterator, iterator> _Pii;
	const size_type __n = _M_bkt_num_key(__key);

	for (_Node* __first = _M_buckets[__n]; __first; __first = __first->_M_next)
		if (_M_equals(_M_get_key(__first->_M_val), __key)) {
			for (_Node* __cur = __first->_M_next; __cur; __cur = __cur->_M_next)
				if (!_M_equals(_M_get_key(__cur->_M_val), __key))
					return _Pii(iterator(__first, this), iterator(__cur, this));
			for (size_type __m = __n + 1; __m < _M_buckets.size(); ++__m)
				if (_M_buckets[__m])
					return _Pii(iterator(__first, this),
					iterator(_M_buckets[__m], this));
			return _Pii(iterator(__first, this), end());
		}
		return _Pii(end(), end());
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
pair<typename hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::const_iterator, 
typename hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::const_iterator> 
hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::equal_range(const key_type& __key) const
{
	typedef pair<const_iterator, const_iterator> _Pii;
	const size_type __n = _M_bkt_num_key(__key);

	for (const _Node* __first = _M_buckets[__n] ;
		__first; 
		__first = __first->_M_next) {
			if (_M_equals(_M_get_key(__first->_M_val), __key)) {
				for (const _Node* __cur = __first->_M_next;
					__cur;
					__cur = __cur->_M_next)
					if (!_M_equals(_M_get_key(__cur->_M_val), __key))
						return _Pii(const_iterator(__first, this),
						const_iterator(__cur, this));
				for (size_type __m = __n + 1; __m < _M_buckets.size(); ++__m)
					if (_M_buckets[__m])
						return _Pii(const_iterator(__first, this),
						const_iterator(_M_buckets[__m], this));
				return _Pii(const_iterator(__first, this), end());
			}
	}
	return _Pii(end(), end());
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
typename hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::size_type 
hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::erase(const key_type& __key)
{
	const size_type __n = _M_bkt_num_key(__key);
	_Node* __first = _M_buckets[__n];
	size_type __erased = 0;

	if (__first) {
		_Node* __cur = __first;
		_Node* __next = __cur->_M_next;
		while (__next) {
			if (_M_equals(_M_get_key(__next->_M_val), __key)) {
				__cur->_M_next = __next->_M_next;
				_M_delete_node(__next);
				__next = __cur->_M_next;
				++__erased;
				--_M_num_elements;
			}
			else {
				__cur = __next;
				__next = __cur->_M_next;
			}
		}
		if (_M_equals(_M_get_key(__first->_M_val), __key)) {
			_M_buckets[__n] = __first->_M_next;
			_M_delete_node(__first);
			++__erased;
			--_M_num_elements;
		}
	}
	return __erased;
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
void hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::erase(const iterator& __it)
{
	_Node* __p = __it._M_cur;
	if (__p) {
		const size_type __n = _M_bkt_num(__p->_M_val);
		_Node* __cur = _M_buckets[__n];

		if (__cur == __p) {
			_M_buckets[__n] = __cur->_M_next;
			_M_delete_node(__cur);
			--_M_num_elements;
		}
		else {
			_Node* __next = __cur->_M_next;
			while (__next) {
				if (__next == __p) {
					__cur->_M_next = __next->_M_next;
					_M_delete_node(__next);
					--_M_num_elements;
					break;
				}
				else {
					__cur = __next;
					__next = __cur->_M_next;
				}
			}
		}
	}
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
void hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::erase(iterator __first, iterator __last)
{
	size_type __f_bucket = __first._M_cur ? 
		_M_bkt_num(__first._M_cur->_M_val) : _M_buckets.size();
	size_type __l_bucket = __last._M_cur ? 
		_M_bkt_num(__last._M_cur->_M_val) : _M_buckets.size();

	if (__first._M_cur == __last._M_cur)
		return;
	else if (__f_bucket == __l_bucket)
		_M_erase_bucket(__f_bucket, __first._M_cur, __last._M_cur);
	else {
		_M_erase_bucket(__f_bucket, __first._M_cur, 0);
		for (size_type __n = __f_bucket + 1; __n < __l_bucket; ++__n)
			_M_erase_bucket(__n, 0);
		if (__l_bucket != _M_buckets.size())
			_M_erase_bucket(__l_bucket, __last._M_cur);
	}
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
inline void
hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::erase(const_iterator __first,
											 const_iterator __last)
{
	erase(iterator(const_cast<_Node*>(__first._M_cur),
		const_cast<hashtable*>(__first._M_ht)),
		iterator(const_cast<_Node*>(__last._M_cur),
		const_cast<hashtable*>(__last._M_ht)));
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
inline void
hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::erase(const const_iterator& __it)
{
	erase(iterator(const_cast<_Node*>(__it._M_cur),
		const_cast<hashtable*>(__it._M_ht)));
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
void hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::resize(size_type __num_elements_hint)
{
	const size_type __old_n = _M_buckets.size();
	if (__num_elements_hint > __old_n) {
		const size_type __n = _M_next_size(__num_elements_hint);
		if (__n > __old_n) {
			vector<_Node*, _All> __tmp(__n, (_Node*)(0),
				_M_buckets.get_allocator());
			__STL_TRY {
				for (size_type __bucket = 0; __bucket < __old_n; ++__bucket) {
					_Node* __first = _M_buckets[__bucket];
					while (__first) {
						size_type __new_bucket = _M_bkt_num(__first->_M_val, __n);
						_M_buckets[__bucket] = __first->_M_next;
						__first->_M_next = __tmp[__new_bucket];
						__tmp[__new_bucket] = __first;
						__first = _M_buckets[__bucket];          
					}
				}
				_M_buckets.swap(__tmp);
			}
		}
	}
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
void hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::_M_erase_bucket(const size_type __n, 
															_Node* __first, 
															_Node* __last)
{
	_Node* __cur = _M_buckets[__n];
	if (__cur == __first)
		_M_erase_bucket(__n, __last);
	else {
		_Node* __next;
		for (__next = __cur->_M_next; 
			__next != __first; 
			__cur = __next, __next = __cur->_M_next)
			;
		while (__next != __last) {
			__cur->_M_next = __next->_M_next;
			_M_delete_node(__next);
			__next = __cur->_M_next;
			--_M_num_elements;
		}
	}
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
void hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::_M_erase_bucket(const size_type __n,
															_Node* __last)
{
	_Node* __cur = _M_buckets[__n];
	while (__cur != __last) {
		_Node* __next = __cur->_M_next;
		_M_delete_node(__cur);
		__cur = __next;
		_M_buckets[__n] = __cur;
		--_M_num_elements;
	}
}

template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
void hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::clear()
{
	for (size_type __i = 0; __i < _M_buckets.size(); ++__i) {
		_Node* __cur = _M_buckets[__i];
		while (__cur != 0) {
			_Node* __next = __cur->_M_next;
			_M_delete_node(__cur);
			__cur = __next;
		}
		_M_buckets[__i] = 0;
	}
	_M_num_elements = 0;
}


template <class _Val, class _Key, class _HF, class _Ex, class _Eq, class _All>
void hashtable<_Val,_Key,_HF,_Ex,_Eq,_All>::_M_copy_from(const hashtable& __ht)
{
	_M_buckets.clear();
	_M_buckets.reserve(__ht._M_buckets.size());
	_M_buckets.insert(_M_buckets.end(), __ht._M_buckets.size(), (_Node*) 0);
	__STL_TRY {
		for (size_type __i = 0; __i < __ht._M_buckets.size(); ++__i) {
			const _Node* __cur = __ht._M_buckets[__i];
			if (__cur) {
				_Node* __copy = _M_new_node(__cur->_M_val);
				_M_buckets[__i] = __copy;

				for (_Node* __next = __cur->_M_next; 
					__next; 
					__cur = __next, __next = __cur->_M_next) {
						__copy->_M_next = _M_new_node(__next->_M_val);
						__copy = __copy->_M_next;
				}
			}
		}
		_M_num_elements = __ht._M_num_elements;
	}
	__STL_UNWIND(clear());
}

_END_HS_NAMESPACE_

#endif